Quick answer
Compare HVAC quotes by first making them describe the same job: same capacity, same efficiency ratings, same matched indoor and outdoor models. Then line up the inclusions, because most of the price gap comes from missing lines — permit, disposal, a new plenum, venting, electrical — rather than the equipment. Read the labour warranty and who files the rebates before you read the total.
To compare HVAC quotes properly you have to make them describe the same work before you look at the bottom line. Three prices for a new furnace can sit thousands apart and all be honest, because one carries the permit, a fabricated plenum and a chimney liner while another carries none of them. Put them side by side on four things — equipment, inclusions, warranty and rebate handling — and the cheapest number often stops being the cheapest job.
First, confirm they are quoting the same system
- Model numbers for every piece: furnace, indoor coil, condenser or heat pump. The phrase 'high-efficiency two-stage' is a description, not a specification.
- Capacity in BTU or tons, and where it came from. A larger furnace is not a better furnace — see can a furnace be too big for my house.
- Efficiency ratings: AFUE on the furnace, SEER2 and HSPF2 on anything that cools or heat-pumps
- A matched system — the indoor coil and outdoor unit rated to work together, not two parts that happen to bolt up
- Staging and blower type, since a two-stage furnace with a variable-speed blower is a quieter, steadier machine than a single-stage unit at the same price point
Second, line up the inclusions — this is where the money hides
- Permit and inspection, typically $100–$300, and whether the contractor pulls it
- Removal and disposal of the old equipment, worth $150–$400
- New plenum and sheet-metal transitions, or a note saying the existing ones are being reused
- PVC intake and exhaust venting, condensate drain, trap and pump if the floor drain is uphill
- Electrical work — a new circuit, a disconnect, or a surge protector on a heat pump
- A chimney liner or a power-vent conversion for the water heater when the tank is orphaned by a high-efficiency furnace
- Thermostat, filter rack and the first filter, plus the start-up and gas-pressure report
Two more lines belong on the same page: the timeline, and the payment terms. A quote that can start next week and a quote that starts in five weeks are not the same product in February, and a deposit of half the job up front is a different risk than a deposit on ordering with the balance on commissioning. Write both onto your comparison sheet beside the totals.
Third, read both warranties, not just the price
10 years of parts with one year of labour is a different offer than 10 and 10, and the difference shows up the first time a blower motor fails on a Tuesday in February. Ask who registers the equipment and by what date, and ask what the labour coverage does not include. Our breakdown of a labour warranty versus a parts warranty covers the fine print worth arguing about.
Fourth, ask who files the rebates
The current Ontario program pays only on qualifying models — check the product list on the program page — and the money arrives after the install, not off the invoice. A quote that names the exact rebate you qualify for and files the paperwork is worth more than one that says 'rebates available' in the footer. Current programs run $500–$7,500 depending on the system — see the Home Renovation Savings Program for what is live right now.
The quote that looks cheapest and is not
Picture a Millcroft two-storey with a 1990s mid-efficiency furnace and a gas water heater sharing the chimney. A complete quote replaces the furnace, liners or power-vents the tank, fabricates a new plenum and pulls the permit. A thinner quote does the furnace only, and the homeowner meets the liner as a change order after the drywall dust settles.
Watch for two other tells: a price that expires when the salesperson walks out the door, and a total with no itemization behind it. A written quote you can read the next morning is the minimum standard.
Common questions about comparing HVAC quotes
- How many quotes should I get? Three is enough to see the spread. Give each contractor the same information — the model of the old unit, photos of the venting, the panel and the water heater — so the differences are in the quotes rather than in what each one had to guess.
- Is the cheapest quote ever the right one? Yes, when the inclusions match. A contractor with lower overhead, or a base-tier brand at the same AFUE and SEER2, can be cheaper and complete; the tell is a missing line, not a low number.
- Should I ask for the load calculation? Yes — a quote that sizes the furnace off the old badge repeats a 1990s oversizing. Ask for the CSA F280 heat loss on paper and check that the furnace and coil on the quote match it.
We are happy to be one of your three quotes. Ours arrives itemized, with model numbers, permit and disposal on the page, and the rebate you qualify for named — see furnace installation for what the day looks like, read how contractors price a job before you compare, and request your written quote when you are ready.